Craig, my ISP doesn't do anything of this kind; also my local broadband connection is rather straight-forward. Never experienced problem with other webpages that are indeed up and running; can you suggest any work-around? Like, do they have resellers for ShotPut Express?

Blocking doesn't have to happen by your ISP. DNS issues can crop up for all sorts of reasons. I've had it happen on rare occasion.

Try this. I've used it in a pinch when I had what I believed were DNS issues.
http://www.opendns.com/

I delete the clips using the camera. In the others menu go to clips and then delete all clips. This leaves the camera settings on the card.

Just got word back from ShotPut EXpress re my worry about losing my camera settings if I use their very convenient 'reformat' card option:

"The "reformat" only erases the contents of the BPAV folder. Your camera settings will be preserved"